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          <th colspan="3" align="center">DB-&gt;truncate()</th>
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                The DB Handle
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            <h2 class="title" style="clear: both"><a id="dbtruncate"></a>DB-&gt;truncate()</h2>
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      <pre class="programlisting">#include &lt;db.h&gt;

int
DB-&gt;truncate(DB *db,
    DB_TXN *txnid, u_int32_t *countp, u_int32_t flags);  </pre>
      <p>
         The <code class="methodname">DB-&gt;truncate()</code> method empties the database, discarding all
         records it contains.  The number of records discarded from the
         database is returned in <span class="bold"><strong>countp</strong></span>.
    </p>
      <p>
         When called on a database configured with secondary indices using the
         <a class="xref" href="dbassociate.html" title="DB-&gt;associate()">DB-&gt;associate()</a> 
         method, the <code class="methodname">DB-&gt;truncate()</code> method truncates the primary database and
         all secondary indices.  A count of the records discarded from the
         primary database is returned.
    </p>
      <p>
         It is an error to call the <code class="methodname">DB-&gt;truncate()</code> method on a database with
         open cursors.
    </p>
      <p>
         The <code class="methodname">DB-&gt;truncate()</code> <span>
            <span>
                  method returns a non-zero error value on failure and 0 on success.
            </span>
            
        </span>
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      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idp50719552"></a>Parameters</h3>
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              <div>
                <h4 class="title"><a id="idp50719744"></a>txnid</h4>
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          <p>
                          If the operation is part of an application-specified transaction, the
                          <span class="bold"><strong>txnid</strong></span> parameter is a transaction
                          handle returned from <a class="xref" href="txnbegin.html" title="DB_ENV-&gt;txn_begin()">DB_ENV-&gt;txn_begin()</a>; if the
                          operation is part of a Berkeley DB Concurrent Data Store group, the
                          <span class="bold"><strong>txnid</strong></span> parameter is a handle returned
                          from <a class="xref" href="envcdsgroup_begin.html" title="DB_ENV-&gt;cdsgroup_begin()">DB_ENV-&gt;cdsgroup_begin()</a>;
                          otherwise NULL. If no transaction handle is specified, but the
                          operation occurs in a transactional database, the operation will be
                          implicitly transaction protected.
                     </p>
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              <div>
                <h4 class="title"><a id="idp50712192"></a>countp</h4>
              </div>
            </div>
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          <p>
                          The <span class="bold"><strong>countp</strong></span> parameter references
                          memory into which  the number of records discarded from the database
                          is copied.
                     </p>
        </div>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
            <div>
              <div>
                <h4 class="title"><a id="idp50708272"></a>flags</h4>
              </div>
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          <p>
                          The <span class="bold"><strong>flags</strong></span> parameter is currently
                          unused, and must be set to 0.
                     </p>
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      <div class="sect2" lang="en" xml:lang="en">
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              <h3 class="title"><a id="idp50705504"></a>Errors</h3>
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        <p>
                         The <code class="methodname">DB-&gt;truncate()</code> <span>
            <span>
                 method may fail and return one of the following non-zero errors:
            </span>
            
        </span>
                    </p>
        <div class="sect3" lang="en" xml:lang="en">
          <div class="titlepage">
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              <div>
                <h4 class="title"><a id="idp50727184"></a>DB_LOCK_DEADLOCK</h4>
              </div>
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          <p>
                A transactional database environment operation was selected to resolve
                a deadlock.
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                <h4 class="title"><a id="idp50734968"></a>DB_LOCK_NOTGRANTED</h4>
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          <p>
                A Berkeley DB Concurrent Data Store database environment configured
                for lock timeouts was unable to grant a lock in the allowed time.
            </p>
          <p>
                You attempted to open a database handle that is configured
                for no waiting exclusive locking, but the exclusive lock could not be
                immediately obtained. See
                <a class="xref" href="dbset_lk_exclusive.html" title="DB-&gt;set_lk_exclusive()">DB-&gt;set_lk_exclusive()</a>
                for more information.
            </p>
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        <div class="sect3" lang="en" xml:lang="en">
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            <div>
              <div>
                <h4 class="title"><a id="idp50728520"></a>EINVAL</h4>
              </div>
            </div>
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          <p>
                If there are open cursors in the database; or if an invalid flag value or parameter was specified.
            </p>
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              <h3 class="title"><a id="idp50724984"></a>Class</h3>
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                <a class="link" href="db.html" title="Chapter 2.  The DB Handle">DB</a>  
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              <h3 class="title"><a id="idp50729376"></a>See Also</h3>
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        <p>
                     <a class="xref" href="db.html#dblist" title="Database and Related Methods">Database and Related Methods</a> 
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